You can digest starch but you cannot digest ce11u1οse. why?

Cellulose is a lot stronger than starch. Starch is practically useless as a material, but celluose is strong enough to make fibers from, and hence rope, clothing, etc. Cellulose doesn't dissolve in water the way starch will, and doesn't break down as easily.
Your body contains enzymes that break starch down into glucose to fuel your body. But we humans don't have enzymes that can break down cellulose.

The answer is going to be a because ik that i’m right

An ecosystem is in a certain area and includes living and non living plus there is weather conditions and a biome is a large amount of area with similar climate.so ecosystem is based on weather and biome is based on the average climate